https://whatis.techtarget.com/definition/backdoor-selling
Backdoor selling is a social engineering practice used by a supplier or seller to gain a competitive advantage prior to negotiations or competition for a contract or sale. The practice reduces the buyer’s leverage and the need for negotiation, thereby often assuring a contract or getting a better price for the seller.
Backdoor selling involves asking questions to acquire information that the buyer wants to protect or that competitors lack. The salesperson would not generally target employees involved with procurement but other staff who are unlikely to recognize the value of the information sought.
https://thebusinessprofessor.com/sales/back-door-selling-def...

Back door selling is defined as a strategy used by sales personnel to extract information about a company in order to have an edge over other investors. This is a dishonest tactic and it is regarded illegal. Sellers use this strategy to cleverly extract information that the buyer might ordinarily not want to disclose. Through the means of enticement and other tactics, sales personnel gain information that put them at an edge over competitors and even the buyers involved. Also, sales personnel can also have buyers purchase their goods without any competitive bidding or negotiation through the back door selling.

Probando con una traducción literal, en un sitio español, aparece:

Aspectos éticos y legales en las ventas - Studylibhttps://studylib.es › doc ›

Ética y relaciones en las ventasVentas por la puerta trasera:Es cuando ignoran la política del agente de compras, pasan por detrás de él y se ponen en contacto con otras personas que intervienen en la decisión de compra.www.rrhh-web.com

y hay más:


(PDF) TECNICAS DE VENTA RESUMEN 3P | VICTOR HUGO ...https://www.academia.edu › ...
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... obsequios Difamación comercial Tratamiento especial Información confidencial Reciprocidad Ventas por la puerta trasera Cuentas de gastos ...

Primer y Segundo Parcial Ventas - DOKUMEN.TIPShttps://dokumen.tips › Documents
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...TRATAMIENTO ESPECIAL INFORMACION CONFIDENCIAL VENTAS POR LA PUERTA TRASERA ETICA 2CUENTA DE GASTOS ...

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